Connecting plate for a battery holder

ABSTRACT

A connecting plate has: bus bars which connect a plurality of batteries; a voltage-detection terminal unit which is connected to the bus bars and through which a voltage of a desired one of the batteries is detected; an electric wire connected to the voltage-detection terminal unit; and a molded resin board to which these components are integrally fixed. In the voltage-detection terminal unit, a device mounting portion onto which a circuit protecting device is to be mounted is integrally formed between an overlap contact portion opposed to the bus bar, and an electric wire connecting portion. Resin leakage preventing pieces for the bus bars are formed at side edges of the overlap contact portion. A device mounting portion is exposed to an outside through a device mounting window which is opened in the molded resin board, and a circuit protecting device is housed in the device mounting window.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a connecting plate which is used withbeing mounted onto a battery holder housing a large number ofcylindrical batteries for an electric vehicle or the like.

The present application is based on Japanese Patent Application No. Hei.9-279259, which is incorporated herein by reference.

2. Description of the Related Art

As a member for connecting plural batteries in series or in parallel,conventionally, a connecting plate 100 shown in FIGS. 25(A) and 25(B) isproposed.

The connecting plate 100 comprises a molded resin board 103 and bus bars102 which are integrally molded with a resin. The bus bars 102respectively connect to two batteries 101. In the molded resin board103, a hexagonal window 103a and a rectangular window 103b through whichelectrode holes 102a at the ends of the batteries 101 are exposed areformed. The two batteries 101 are connected to each other by fasteningthe bus bars 102 respectively to nut-shaped positive and negativeelectrodes 101a and 101b by bolts 104. Also, a ring terminal 105partially constituting a voltage detection circuit is connected to oneof the windows or the hexagonal window 103a. A fuse case 107 isconnected in series to the other end side of an electric wire 106 whichis connected at one end to the ring terminal 105. The other end of theelectric wire is connected to an ECU which is not shown. A fuse 108 ishoused in the fuse case 107. The ends of the fuse are connected toelectrical contact portions 109a of female terminals 109 connected tothe electric wire 106, respectively.

FIG. 26 shows another example of a conventional connecting plate.

In the connecting plate 100', plural L-shape bus bars 102' respectivelyhaving connecting legs 102b' of different lengths are moldingly fixed bya molded resin board 103. One end of each of the connecting legs 102b'protrudes from one side edge of the molded resin board 103. Ends on oneside of electric wires 106 are welded to the protruding ends,respectively. The other ends of the wires are connected via a fuse case108' to an ECU which is not shown.

In the fuse case 108', two L-shape pressure contact terminals 111 areopposingly disposed on a case substrate 110. The electric wires 106 arewelded to basal plates 111a of the pressure contact terminals 111,respectively. Lead wires 108a' of fuses 108 are connected by pressurecontact to slots 11c of pressure contact pieces 111b upstanding from thebasal plates 111a, respectively.

The connecting plate 100 of FIG. 25 has many connecting portions in onecircuit. In the voltage detection circuit, for example, there are sixconnecting portions indicated by letters a, b, . . . , and f. The numberof parts is large. Therefore, there is a fear that the reliability ofelectrical connection is impaired. Furthermore, a work of fasteningbolts must be conducted while holding respective ring terminals 105 oneby one by a hand. As the number of electric wires to be connected islarger, therefore, the works of laying and routing the electric wiresbecome more cumbersome and difficult.

By contrast, in the connecting plate 100' of FIG. 26, the L-shape busbars 102' of different dimensions are used. Therefore, the plate hasdifficulties in cost and production management. In the same manner asthe connecting plate 100, the number of parts is large and there aremany connecting portions in one circuit (five portions a', b', . . . ,e'). Moreover, the connecting plate has a problem in that the weldingportions between the electric wires 106 and the connecting legs 102b'must be protected.

Furthermore, the electric wires 106 for the connecting plates 100 and100' are directly connected to the batteries 101, and therefore anadequate protecting structure may be required. However, such protectingstructure is complicated since bulky members such as the fuse cases 107and 108' are attached to the electric wires 106.

FIG. 27 shows a structure in which batteries for an electric vehicle orthe like are directly connected to one another without using connectingplates. In each of rectangular batteries 101', the positive and negativeelectrodes 101a' and 101b' are juxtaposed in one end side. Adjacentbatteries are connected to each other by a main power source wire 112.An electric wire 106 (a voltage detection circuit) which has a fuse case107 in the same manner as FIG. 25 is connected to a required electrode101b'.

Also in this case, in the same manner as described above, the number ofparts is large (the voltage detection circuit). Since the electric wireshave many exposed portions, it is dangerous. Furthermore, the main powersource wire 112 and the electric wire 106 of the voltage detectioncircuit intersect with each other, so that the wiring is complicated.This often causes the wiring to be erroneously conducted.

In order to solve these problems, it may be contemplated that, in theconnecting plate 100 or 100', the connecting wire 106 is insert-moldedin the molded resin board 103, and a fuse 108 or 108' serving as acircuit protecting device is interposed between the bus bar 102 or 102'and the connecting wire 106.

In order to connect the fuse 108 or the like, another terminal must bedisposed between the bus bar and the connecting wire. It is preferableto surely electrically connect this terminal with the bus bar withoutusing fastening or welding means and at the same time with the insertmolding.

SUMMARY OF THE INVENTION

The invention has been conducted in view of the above-discussedproblems. An object of the present invention is to provide a connectingplate having a structure in which a bus bar connecting batteries, avoltage-detection terminal unit partially constituting a voltagedetection circuit, and the like are integrally insert-molded by a resin,and hence there are a reduced number of exposed portions so as toenhance the safety and facilitate the assembly work, and in which atrouble such as that, in the insert molding, a resin enters between thebus bar and the voltage-detection terminal unit to cause a failure ofcontinuity does not occur.

In order to achieve the object, according to the present invention,there is provided a connecting plate for a battery holder comprising: abus bar which connects a plurality of batteries; a voltage-detectionterminal unit which is connected to the bus bar and through which avoltage of a desired one of the batteries is detected; an electric wireconnected to the voltage-detection terminal unit; and a molded resinboard to which these components are integrally fixed, wherein thevoltage-detection terminal unit includes a resin leakage preventingpiece formed at a side edge of a contact portion of thevoltage-detection terminal unit and opposed to the bus bar, the resinleakage preventing piece serving also as a positioning piece withrespect to the bus bar.

A device mounting portion onto which a circuit protecting device is tobe mounted may be provided. The device mounting portion is integrallyformed with the voltage-detection terminal unit between the contactportion and an electric wire connecting portion, the device mountingportion being exposed to an outside through a device mounting windowwhich is opened in the molded resin board, and a circuit protectingdevice mounted onto the device mounting portion being housed in thedevice mounting window.

The bus bar, the voltage-detection terminal unit connected to the busbar, the wire connecting the bar and the terminal, and the like areintegrally molded by a resin, and hence a connecting plate having astructure in which there are a reduced number of exposed portions, thesafety is enhanced, and the assembly work is facilitated is obtained.

Since the resin leakage preventing piece serving also as a positioningpiece with respect to the bus bar is formed so as to be bent at a sideedge of the overlap contact portion, the voltage-detection terminal unitcan be easily positioned with respect to the bus bar, thereby improvingthe workability. When, in an insert molding, the flow direction of amolten resin is set so as to be perpendicular to the resin leakagepreventing piece, the molten resin is prevented from entering betweenthe bus bar and the overlap contact portion, thereby eliminating afailure of continuity.

Preferably, in the overlap contact portion of the voltage-detectionterminal unit and opposed to the bus bar, resin leakage inspection holesare formed around a bolt insertion hole at the center.

In this configuration, the formation of the resin leakage inspectionholes enables an entrance of a molten resin between the bus bar and theoverlap contact portion to be checked through the holes. When the resinleakage inspection holes are increased in size or the area of the holesis increased, the pressure of a molten resin entering the holes israpidly lowered, and hence the molten resin is prevented from furtheradvancing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a battery holder having aconnecting plate for a battery holder which is an embodiment of thepresent invention;

FIG. 2 is a perspective view of the connecting plate for a batteryholder of FIG. 1;

FIG. 3 is an enlarged perspective view of main portions of theconnecting plate of FIG. 2;

FIG. 4 is an enlarged perspective view showing a connecting state of abus bar, a voltage-detection terminal unit, and a circuit protectingdevice which are shown in FIG. 3;

FIG. 5(A) is a circuit diagram showing connections of batteries andvoltage-detection terminal units in connecting plates 10 and 10' of FIG.1;

FIG. 5(B) is a circuit diagram showing connections of PTC devices fordetecting heat generation in a battery;

FIG. 6 is a view illustrating a production step (pretreatment step) ofthe connecting plate for a battery holder of FIG. 1;

FIG. 7 is a view illustrating a production step (connection of terminalsand fitting to case) subsequent to that of FIG. 6;

FIG. 8 is a view illustrating a production step (a step of wiring aharness for a plate) subsequent to that of FIG. 7;

FIG. 9 is a view illustrating a production step (a primary molding)subsequent to that of FIG. 8;

FIG. 10 is a perspective view of main portions of a primary moldedproduct obtained in the step of FIG. 9;

FIG. 11 is a view illustrating a production step (a secondary molding)subsequent to that of FIG. 9;

FIG. 12 is a plan view showing a state in which the primary moldedproduct of FIG. 11 is set in a mold;

FIGS. 13(A) to 13(D) show the final production step (a step of mountinga circuit protecting device), FIG. 13(A) is a plan view of a window formounting a circuit protecting device, FIG. 13(B) is a perspective viewof the window, FIG. 13(C) is a section view of the window, and FIG.13(D) is a section view showing a state in which the circuit protectingdevice is connected;

FIGS. 14(A) and 14(B) show a manner of leading out connecting wires ofthe connecting plate for a battery holder of FIG. 2, FIG. 14(A) is aperspective view of main portions of a primary molded product P₁, andFIG. 14(B) is a perspective view of main portions of a secondary moldedproduct P₂ ;

FIGS. 15(A) and 15(B) show another embodiment of the primary moldingstep of FIG. 9, FIG. 15(A) is a perspective view of main portions ofupper and lower molds using a rubber mat, and FIG. 15(B) is an explodedperspective view of the main portions;

FIG. 16 is a section view showing another embodiment of the rubber mat;

FIGS. 17(A) and 17(B) show a supplementary embodiment of the primarymolding step of FIG. 9, FIG. 17(A) is a perspective view of mainportions of an upper (lower) mold using another rubber mat, and FIG.17(B) is a section view of the main portions;

FIG. 18 shows another supplementary embodiment of the primary moldingstep of FIG. 9 and is a view illustrating a method of supplying a resinto molds;

FIGS. 19(A) and 19(B) show main portions and illustrates a structure forconnecting the bus bar, the voltage-detection terminal unit, and thecircuit protecting device in the connecting plate for a battery holder,FIG. 19(A) is a perspective view showing the secondary molding, and FIG.19(b) is a perspective view showing the final step;

FIG. 20(A) is a section view taken along the line X--X of FIG. 19(B);

FIG. 20(B) is a section view taken along the line Y--Y of FIG. 19(B) andshowing a state in which the circuit protecting device is attached;

FIGS. 21(A) and 21(B) are views illustrating another structure forconnecting the bus bar, the voltage-detection terminal unit, and thecircuit protecting device in the connecting plate for a battery holder;

FIGS. 22(A) and 22(B) show a structure for relaxing stress in thevoltage-detection terminal unit of the connecting plate for a batteryholder of FIG. 1, FIG. 22(A) is a perspective view of main portions, andFIG. 22(B) is a section view taken along the line X--X of FIG. 22(A);

FIGS. 23(A) and 23(B) show another structure for relaxing stress in thevoltage-detection terminal unit, FIG. 23(A) is a perspective view ofmain portions, and FIG. 23(B) is a longitudinal section view;

FIGS. 24(A) to 24(C) show a further structure for relaxing stress in thevoltage-detection terminal unit, FIG. 24(A) is a perspective view of avoltage-detection terminal unit 17', and FIGS. 24(B) and 24(C) arelongitudinal section views respectively showing states of attaching theterminal to window frames 14' and 14";

FIG. 25(A) is a perspective view showing main portions of an example ofa conventional connecting plate for a battery holder;

FIG. 25(B) is a longitudinal section view of a fuse holder shown in FIG.25(A);

FIG. 26 is a perspective view showing main portions of another exampleof a conventional connecting plate for a battery holder; and

FIG. 27 is a view showing another example of conventional connectingbatteries.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, preferred embodiments of the present invention will now bedescribed with reference to FIGS. 1 to 24(C).

Referring to FIG. 1, A denotes a long cylindrical battery which is to beused in an electric vehicle or the like, and B denotes a battery holderfor housing a large number of batteries A. In each of the batteries A,nut-shaped positive and negative electrodes 2a and 2b having a femalethread are disposed at the ends of the body 1, respectively. A PTCdevice 3 is embraced by and fixed to the outer periphery of the body 1in order to check heat generation of the battery A.

The battery holder B comprises a rectangular frame-like main unit 4, andconnecting plates 10 and 10' which are attached to the sides of the mainunit, respectively. In the illustrated example, the frame-like main unit4 has a frame structure in which plural support plates 6 where arearranged in parallel and in a row by using stays 7. In each of thesupport plates, eighteen battery insertion holes 5 in total are openedin a matrix of 6 holes in vertical and 3 holes in lateral. Plural bolts9 for fixing the battery holder to the vehicle body are implanted in oneside wall 8 extending in the longitudinal direction.

FIG. 2 is a perspective view of the connecting plate 10, FIG. 3 is anenlarged view of main portions of the plate, and FIG. 4 is a perspectiveview showing a connecting state of a bus bar, a voltage-detectionterminal unit, and a circuit protecting device which are shown in FIG.3.

The connecting plate 10 (10') is configured by inserting and fixing busbars 16 and 16' (see FIG. 12) connecting the plural batteries,voltage-detection terminal units 17, fuses 21 serving as circuitprotecting devices, connecting wires 22, and the like, into a moldedresin board 11.

In the molded resin board 11, hexagonal windows 12 and rectangularwindows 12' for connecting electrodes are formed in accordance with thearrangement of the plural batteries A. A rectangular window 13 forconnecting the PTC device is formed at the side of each of the windows12 and 12'. Two fuse mounting windows 14 are juxtaposed between desiredhexagonal and rectangular windows which are denoted by 12₁ and 12₁ '.Connecting pieces 15 for connecting the PTC devices 3 in series areembedded between adjacent rectangular windows 13, and connectingendportions 15a at the ends and having a connection hole 15b are exposedthrough the rectangular windows 13. The fuses 21 are housed in the fusemounting windows 14, respectively.

Each of the bus bars 16 is formed as a link-like plate member throughwhich a large current can flow. A battery connection hole 16a is formedat each end. The bus bars are arranged at intervals corresponding to thearrangement of the batteries A. The bus bars 16' are formed into aU-like shape so as to connect adjacent batteries A in a vertical row.

Among the plural bus bars 16 (16'), for example, bus bars denoted by 16₁are connected to the voltage-detection terminal units 17, respectively.

Each of the voltage-detection terminal units 17 (see FIG. 6) comprisesan overlap contact portion 18 opposed to the corresponding bus bar 16, adevice mounting portion 19 which is continuous to the overlap contactportion, and a wire connecting portion 20. These portions are integrallyformed by punching or bending an electrically conductive metal plate.

The overlap contact portion 18 is formed as a square or rectangularplate member of a size which enables the portion to be substantiallyoverlapped to an end portion of the bus bar 16. A bolt insertion hole18a having the same diameter as the battery connection hole 16a isformed in a center portion. Plural (in the illustrated example, four)resin leakage inspection holes 18b of a small diameter are formed aroundthe hole 18a. Resin leakage preventing pieces 18c and 18c' which servealso as positioning pieces are downwardly bent and formed in two edgesof the overlap contact portion 18 which perpendicularly intersect witheach other. When the pieces 18c and 18c' abut against side edges of theend portion of the bus bar 16, the center of the bolt insertion hole 18ais automatically made coincident with that of the battery connectionhole 16a.

The device mounting portion 19 is continuously formed via a connectionpiece 18d which is downward cranked, on the resin leakage preventingpiece 18c' which is on one of the two adjacent edges of the overlapcontact portion 18. The device mounting portion 19 includes a pair oflead connecting pieces 19a opposed to leads 21b of the ends of the fuse21, and a connecting piece 19b which integrally holds the two connectingpieces. A lead connection hole 19c is formed in each of the leadconnecting pieces 19a. The device mounting portion 19 is made lower inlevel than the overlap contact portion 18 by the connection piece 18dand one of the lead connecting pieces 19a, and elongates in parallelwith the resin leakage preventing piece 18c'. The wire connectingportion 20 is formed continuously with the other lead connecting piece19a. One end of the insulated wire 22 is connected to a pair of a wirebarrel 20a and an insulation barrel 20b of the wire connecting portion20, by crimping or the like. The other end side of the wire 22 is laidtogether with the other wires so as to be led out to one side edge 11aof the molded resin board 11. The wires are held at the side edge by awire holder 23 so as to be arranged at given intervals.

The device mounting portion 19 of the voltage-detection terminal unit17, i.e., the pair of the lead connecting pieces 19a and the connectingpiece 19b are exposed through the fuse mounting window 14 of the moldedresin board 11. A pair of fuse engaging arms 24 which have at the upperend a hook-like engaging projection 24a are integrally formed on theinner walls 14a (see FIG. 13) which are on both the sides of the windowand sandwich the connecting piece 19b, respectively.

After insert molding of the molded resin board 11, the connecting piece19b of the device mounting portion 19 is cut away in the fuse mountingwindow 14. The leads 21b of the ends of the fuse 21 are respectivelypassed through the lead connection holes 19c of the remaining leadconnecting pieces 19a at both the sides, and then applied with solder25, whereby the fuse 21 is connected and fixed to the voltage-detectionterminal unit 17. The fuse 21 the leads of which are passed through thelead connection holes 19c is clamped by the pair of fuse engaging arms24, and the hook-like engaging projections 24a, thereby preventing thefuse from slipping off. Even when the molded resin board 11 is turnedupside down, therefore, the fuse is prevented from falling off.Furthermore, a soldering work can be easily conducted.

FIG. 5 is a connection diagram in the case where the batteries A areconnected in series by using the connecting plates 10 and 10', and FIG.5(A) shows a voltage detection circuit for the batteries and FIG. 5(B)shows a temperature detection circuit for the batteries.

Returning to FIG. 1, the batteries A are inserted into the batteryinsertion holes 5 of the battery holder B in such a manner that theirpositive and negative electrodes 2a and 2b are alternatingly inverted.The connecting plates 10 and 10' are set on the electrodes 2a and 2bprotruding from the ends of the holder B, and the ends of the bus bars16 (16') are alternatingly fastened and fixed to the positive andnegative electrodes 2a or 2b of the batteries A by the bolts 26.

As a result, as shown in FIG. 5(A), the batteries A₁, A₂, A₃, . . . ,A_(n) are connected in series by the bus bars 16 (16'). The fuses 21 areconnected to ends of single-pole bus bars 16" and double-pole bus bars16 via the voltage-detection terminal units 17. When the wires 22 areconnected to an ECU which is not shown, therefore, the voltages of allthe batteries A can be always monitored for each sets of two batteries.Batteries A generating an abnormal voltage can be rapidly replaced withother ones in the unit of two batteries.

As described above, the PTC devices 3 are attached to the batteries A₁,A₂, . . . , A_(n), respectively. The lead wires (not shown) of the bothsides of each PTC device are connected to the ends of the connectingpiece 15 in the connecting plate 10 (10'). Specifically, screws whichare not shown are fastened to the connection holes 15b of the connectingend portions 15a at the ends. On the other hand, the lead wires of thePTC device 3 are led out from through paths 13a formed in one side ofthe rectangular windows 13. The lead wires are fixed by the screws.

As a result, as shown in FIG. 5(B), all the PTC devices 3 of thebatteries A₁, A₂, . . . , A_(n), are connected in series. When any oneof the batteries abnormally generates heat, the resistance of the PTCdevice 3 corresponding to the battery is suddenly increased, and hencethe check circuit is opened.

In this way, the embodiment has a structure in which an abnormal voltageand abnormal heat generation of the batteries A in the batter holder Bare always monitored.

Next, a method of producing the connecting plate 10 (10') will bedescribed with reference to FIGS. 6 to 13.

First, the insulated wires 22 which are to be connected to thevoltage-detection terminal units 17 of the connecting plate 10 areprepared. For the convenience of maintenance and the like, preferably,different colors or markers such as a pattern, a stripe, or a symbol areapplied to the insulating coating of the wires 22. The wires are cutinto a predetermined length and the coating at each end is peeled off.

Next, as shown in FIG. 6, the exposed core wire 22a at one end isconnected to the wire connecting portion 20 of the voltage-detectionterminal unit 17, and a female (or male) connector terminal 30 isconnected to the other end, thereby producing a terminal-equipped wire22'.

As shown in FIG. 7, the connector terminals 30 of the thus preparedterminal-equipped wires 22' are then inserted into and engaged with aterminal chamber (not shown) of a connector (housing) 31. The engagingstructure between the connector terminals and the terminal chamber maybe formed in accordance with known means, and hence its illustration isomitted.

Next, as shown in FIG. 8, the voltage-detection terminal units 17 of theterminal-equipped wires 22' are arranged on a wiring table 32 inaccordance with the arrangement positions of the bus bars 16 (16') towhich the terminal-equipped wires are connected to be overlapped. Thewires 22' connected to the voltage-detection terminal units 17 are laidso as to be combined in a center portion of the molded resin board 11,in order to lead out the wires from one side edge of the board. Thewires are combined into a flat shape by tapes 33 to form a harness 34for a plate.

The above will be described in more specifically. In the battery holderB of FIG. 1, the number and positions of the battery insertion holes 5of the support plate 6 are predetermined, and hence also the layout ofthe bus bars 16 and 16' in the connecting plate 10 is uniquelydetermined. In accordance with the layout, therefore, a pair ofconnector engaging pins 35, and plural pairs of wire engaging pins 36(36₁ to 36₃) and terminal engaging pins 37 (37₁ to 37₃) are retractablydisposed on the wiring table 32.

These pins 35, 36, and 37 erect from a mounting base which is not shown,and are caused to collectively protrude from and retract into holesformed in the wiring table 32 by raising and lowering the mounting base.

First, second, and third wire engaging pins 36₁, 36₂, and 36₃ which arerespectively paired are linearly arranged at the center of the wiringtable 32 with starting from the side closer to the pair of connectorengaging pins 35. The terminal engaging pins 37₁ to 37₃ are arranged soas to sandwich or on both the sides of the pairs of wire engaging pins36₁ to 36₃. The gap between the engaging pins 36₃ which are remotestfrom the connector engaging pins 35 is smallest. As a pair of pins arecloser to the connector engaging pins 35, the gap between the pins islarger. These gaps respectively form spans in which the wires 22' laidin the gap can be housed in a substantially flat manner.

In the formation of the harness 34 for a plate, the terminal-equippedwires 22' (see FIG. 7) which are previously obtained are moved onto thewiring table 32, the back face (the wire connection side) of theconnector 31 abuts against the pair of connector engaging pins 35, andthe wires 22' are then arranged between the wire engaging pins 36₁,between the pins 36₂, and between the pins 36₃.

Next, the plural wires 22' between the wire engaging pins 363 arearranged so that a flat state in which the wires do not overlap norcross with one another is maintained. The wires are bent at the pins 363to either side into an L-like shape. The bolt insertion holes 18a of theoverlap contact portions 18 in the voltage-detection terminal units 17at the tip end portions of the wires are engaged with the terminalengaging pins 37₃, respectively. Thereafter, the flat portions of thewires 22' are bundled by the tape 33. Also the wires 22' between thewire engaging pins 36₂ and between the pins 36₁ are then processed inthe same manner.

As a result, as shown in FIG. 8, the harness 34 for a plate is formed inwhich the connector 31 is attached to the one-end side of the flatlyarranged wires 22', the other-end sides are branched at given intervalsby bending into an L-like shape in a bilaterally symmetrical manner bythe wire engaging pins 36 and the terminal engaging pins 37, and thevoltage-detection terminal units 17 are connected to the tip ends.

The harness 34 for a plate is detached from the wiring table 32, and, asshown in FIG. 9, then set in a recess 39 of a primary mold 38 to besubjected to the insert molding by a known method (the upper moldcorresponding to the mold 38 is not shown), thereby obtaining a primarymolded product P₁ shown in FIG. 10.

In the connecting plate 10 of FIG. 2, the dimension X between the outervoltage-detection terminal units 17_(o) which are largely separated fromeach other, the dimension Y between the inner terminals 17_(i), and thedimension Z between the terminals 17_(o) which are vertically separatedfrom each other must be correct, and hence severe accuracy is requested.However, it is difficult to perform the insert molding by one stepwhile, from an initial stage, maintaining the accuracy of the dimensionsbetween the many bus bars 16 and 16' and the wire-equippedvoltage-detection terminal units 17.

As apparent from FIG. 10, the primary molded product P₁ is integrallymolded by primary molded resin boards 11A, 11B, 11B', 11C, and 11C' withleaving a part 22A' of the wires 22', and the overlap contact portions18 and the device mounting portions 19 of the voltage-detection terminalunits 17.

Specifically, there exist the wire exposed portions 22A' among theprimary molded resin board 11A in a center portion of the primary moldedproduct P₁, and the primary molded resin boards 11B, 11C, 11B', and 11C'on the lateral sides. Furthermore, there is no tie in the gaps on thelateral sides between the primary molded resin boards 11B and 11C, and11B' and 11C' where the wires 22' do not exist. The gaps constitute freeportions F.

In the primary molded resin board 11A in the center portion, plural pinholes 41 and vertical grooves 42 are formed, and the wire holder 23 isintegrally disposed. The pin holes 41 and the vertical grooves 42 areformed by pins and bosses (both are not shown) which protrude into therecess 39 in order to prevent the wires 22' from, in the insert moldingusing the primary mold 38, being subjected to an excessive force due tothe injection force of the resin, or twined with each other. A wirefixing piece 43 which is indicated by phantom lines is disposed in themold 38, so that, in the primary insert molding, the wires 22' on theside of the connector 31 are prevented from being disturbed and stressconcentration at the outlet of the wire holder 23 is prevented fromoccurring.

In the primary molded resin board 11B (11B'), a window frame 14' forforming a resin non-filled portion, i.e., the fuse mounting window 14 isdisposed, two voltage-detection terminal units 17_(o) and 17_(i) arefixed by the insert molding so as to laterally interpose the windowframe 14' therebetween, the overlap contact portions 18 of the twoterminals are exposed to the outside, and the device mounting portions19 are exposed in the window frame 14'.

By contrast, in the primary molded resin board 11C (11C'), laterallyarranged voltage-detection terminal units 17_(o) and 17_(i) which areconfigured in a similar manner as those of the primary molded resinboard 11B are vertically arranged, so that three or four terminals intotal are fixed by the insert molding.

Any one of the primary molded resin boards 11B 11C of the primary moldedproduct P₁ is configured by fixing two to four voltage-detectionterminal units 17_(o) and 17_(i) which are close to each other, by theinsert molding. Therefore, the terminals can be fixed with substantiallyhigh accuracy of the dimension between the terminals and without beinglargely affected by the kind of the resin.

In the primary molded product P₁, therefore, the dimensions X', Y', andZ' between various terminals in FIG. 10 may be formed so as to be longerthan the dimensions of the connecting plate 10 of the final product ofFIG. 2, by using the wire exposed portions 22A' and the free portions Fas dimension adjusting portions, and the dimensions may be finallyadjusted in the secondary molding.

Next, as shown in FIGS. 11 and 12, the primary molded product P₁ is setin a secondary mold 45, and a secondary insert molding is thenperformed.

In a recess 46 of the secondary mold 45, positioning engaging pins 47and 48 for the bus bars 16 and 16' and the PTC device connecting pieces15 are disposed, and collar engaging pins 49 are disposed at the fourcorners. Moreover, the positioning bosses (not shown) for the pin holes41 and the vertical grooves 42 of the primary molded product P₁ aredisposed. The reference numeral 50 denotes a holder placing groove forthe wire holder 23.

The bus bars 16, 16', and 16", the connecting pieces 15, and a collar 51are correctly positioned and engaged by the various engaging pins 47 to49 in the recess46. Thereafter, the primary molded resin boards 11A to11C, 11B', and 11C' of the primary molded product P₁ are set, and thepositioning of predetermined bus bars 16 and the voltage-detectionterminal units 17 is performed.

The positioning is performed in the following manner. The overlapcontact portions 18 of the voltage-detection terminal units 17 areoverlaid on corner portions of the bus bars 16 and 16' which have beenset, so that the resin leakage preventing pieces 18c and 18c' of each ofthe portions abut against the side edges of the end portion of thecorresponding bus bar 16 or 16' which perpendicularly intersect witheach other, as described above (see FIG. 4).

Next, an upper mold (not shown) which is paired with the secondary mold45 is set on the secondary mold, and the insert molding is thenperformed under predetermined conditions, thereby obtaining a secondarymolded product.

The secondary molded product is different from the completed connectingplate 10 shown in FIG. 2 in that the fuses 21 are not mounted to thefuse mounting windows 14. The illustration of the whole of the secondarymolded product is omitted.

Namely, in the secondary molded product, in the same manner as theconnecting plate 10, the bus bars 16 and 16' and the like for connectingthe electrodes 2a and 2b of the batteries A, and the connecting pieces15 for connecting the PTC devices are embedded together with the primarymolded resin boards 11A to 11C and the like and the free portions F ofthe primary molded product P₁, into the molded resin board 11. Thehexagonal windows 12 and rectangular windows 12' for connecting theelectrodes, and the rectangular windows 13 for connecting the PTCdevices are opened. The device mounting portions 19 of thevoltage-detection terminal units 17 are exposed through the fusemounting windows 14.

When the fuses 21 are mounted to the fuse mounting windows 14 of thesecondary molded product, therefore, the connecting plate 10 which isthe completed product is obtained.

As shown in FIG. 13(A), in the secondary molded product P₂ ' the pair oflead connecting pieces 19a of the device mounting portion 19 areconnected to each other by the connecting piece 19b in the fuse mountingwindow 14. As shown in FIG. 13(B), the connecting piece 19b is cut away,the leads 21a of the fuse 21 are passed through the lead connectionholes 19c of the lead connecting pieces 19a, and at the same time thefuse body unit 21a is pressingly inserted between the pair of fuseengaging arms 24.

As a result, as shown in FIG. 13(C), the fuse body unit 21a is clampedbetween the engaging arms 24, and the hook-like engaging projections 24aserve as stoppers. Consequently, the fuse 21 does not vertically slipoff and is surely clamped.

Even when the secondary molded product P2 is turned upside down as shownin FIG. 13(D), therefore, there arises no fear that the fuse 21 slipsoff, and the solder 25 can be applied very easily.

As a result of the above process, the connecting plate 10 (10') which isthe completed product is obtained.

Since the fuse 21 is clamped by the pair of fuse engaging arms 24 so asto be prevented from slipping off, the secondary molded product P₂ canbe easily stocked and transported.

FIGS. 14(A) and 14(B) show other embodiments of the primary moldedproduct P₁ and the secondary molded product P₂ in which the manner ofleading out the connecting wires in the connecting plate is improved.

In the embodiment of FIG. 14(A), the primary molded resin board 11A inthe center portion of the primary molded product P₁ is configured sothat a fixing frame 51 is formed integrally with one side of the wireholder 23 for binding the wires 22' and a band 115 (see FIG. 14(B)) forbinding the wires 22' is tied to the fixing frame 51 so as to performthe fixation. According to this configuration, even when an externalforce acts on the wires 22', stress concentration at the root portions22B of the wires can be relaxed or blocked.

During transportation or stock in the process of forming the primarymolded product P₁ into the secondary molded product P₂ shown in FIG.14(B), or after the secondary molding is performed and the moldedproduct is embedded into and protected by the molded resin board 11,therefore, the wires 22' are effectively prevented from being broken.

FIGS. 15(A) and 15(B) show another embodiment for stress relaxation.

The primary molded product P₁ of FIG. 15(A) is configured so that, inplace of the wire holder 23 for bundling the wires 22' of the primarymolded resin board 11A into a flat shape, a pair of upper and lower mats52 clamp the wires.

In each of the mats 52, plural wire placing grooves 52b are arranged onone face of a block-like mat body 52a. Each mat is made of an elasticmember having heat resistance, such as silicone rubber. The rear halfportions of the mats 52 which vertically clamp the wires 22' areembedded into the primary molded resin board 11A, and the front halfportions protrude from the resin board 11A. Therefore, stress acting onthe root portions 22B of the wires 22' can be absorbed and relaxed.

As shown in FIG. 15(B), a mat receive groove 53 is formed in the innerside of wire placing grooves 38a of the primary mold 38, and the mats 52are placed in the mat receive groove. Therefore, the primary molding maybe performed by a conventional method.

In the primary molding, the resin which is injected or filled into theprimary mold 38 is blocked by the upper and lower mats 52. Therefore,the interface portions (or edges) between the wire placing grooves 38acan be loosely formed, so that the wires 22' are prevented from beingbit.

FIG. 16 shows another embodiment of the mats for stress relaxation.

In mats 52' shown in FIG. 16, a large number of projections 52c areformed in a staggered manner on one face of each of mat bodies 52a. Theprojections 52c may have any one of shapes such as a cylindrical shape,a prism-like shape, and a semispherical shape. Preferably, theprojections have a semispherical shape.

The mats 52' can be used in the primary molding by using the primarymold 38 having the mat receive groove 53 shown in FIG. 15(B), and attainthe same effects as that of FIG. 15(A).

FIGS. 17(A) and 17(B) show supplementary embodiments of the mats forstress relaxation and the primary mold.

Referring to FIG. 17(A), in each of upper and lower mats 52", pluralwire placing grooves 52b are disposed in one face of a mat body 52a, anda pair of engaging bosses 52d protrude from the opposite face of the matbody. The engaging bosses 52d are provided at the tip end with abulb-like engaging projections 52d₁.

In order to comply with the mats 52", in a primary mold 38', in place ofthe wire placing grooves 38a, plural guide pins 54 are disposed so as toprotrude in front and rear of a mat receive groove 53', and engagingholes 55 corresponding to the engaging bosses 52d of the mats 52" aredisposed.

In the case of the mats 52", when the engaging bosses 52d are stronglypressed against the respective engaging holes 55, the engaging bosses52d at the tip end pass through the engaging holes 55 to be engagedtherewith as shown in FIG. 17(B). Consequently, there is no fear thatthe mats 52" which have been once set slip off. The wires 22' may beplaced so as to separately or one by one pass through between the guidepins 54 which are arranged in front and rear of the mats 52". As aresult, the wires naturally correspond in one to one relationship to thewire placing grooves 52b of the mats 52", and hence the work can besimplified.

FIG. 18 shows a method of supplying a resin to molds in the primarymolding.

Referring to FIG. 18, a resin filling hole 56 which is directed alongthe laying direction of the wires 22' of the harness 34 for a plate (seeFIGS. 8 and 9) in the inner side is opened in a side face of the primarymold 38.

The flow of the molten resin injected from a nozzle 119 of a moldingmachine 118 is directed along the laying direction of the wires 22' asindicated by the arrow lines. According to this configuration, a resinskin is first formed on the surfaces of the wires 22', and hence the hotresin does not thereafter make direct contact with the wires 22'. As aresult, melt fracture of the wire coating portions is eliminated. Unlikethe related art, therefore, it is not required to use a heat resistantmaterial such as a polyimide resin in the insulation coating of thewires 22 (22').

FIGS. 19(A) and 19(B) are perspective views of main portions and showingthe structure for connecting the bus bar 16, the voltage-detectionterminal unit 17, and the fuse 21. FIG. 19(A) shows a state in thesecondary molding, and FIG. 19(B) shows that in the final step. FIGS.20(A) and 20(B) are section views respectively taken along lines X--Xand Y--Y of FIG. 19(B). In order to simplify the drawings, the fuseengaging arms 24 are not shown.

Prior to the secondary insert molding, the voltage-detection terminalunit 17 is positioned with respect to the bus bar 16. This positioningcan be easily performed because, as described above, the two resinleakage preventing pieces 18c and 18c' which perpendicularly intersectwith each other serve as positioning pieces with respect to the bus bar16.

In the secondary molding, a fear that a molten resin enters between theoverlapping faces of the bus bar 16 and the overlap contact portion 18is substantially eliminated by the blocking function due to the resinleakage preventing piece 18c or 18c' which is positioned in the flowdirection of the molten resin. The bus bar and the portion are surelycontacted and fixed by mold fixation.

As shown in FIG. 20(A), even when a molten resin 57 enters between thebus bar 16 and the overlap contact portion 18, the entrance can beeasily checked through the resin leakage inspection holes 18b, whereby adefective product and a failure in the flow can be prevented fromoccurring.

A secondary molded product P₂ which is checked that the resin leakagedoes not occur in the secondary insert molding is processed in thefollowing manner. In the fuse mounting window 14, the connecting piece19b of the device mounting portion 19 is cut away as shown in FIG.19(B). The leads 21a of the fuse 21 are passed through the leadconnection holes 19c of the remaining lead connecting pieces 19a at theends, and then applied with solder 25 as shown in FIG. 20(B).

As seen from the comparison of FIGS. 19(B) and 19(A), the leadconnecting pieces to which the leads 21a at the ends of the fuse 21 areto be connected, i.e., the lead connecting piece 19a on the side of theoverlap contact portion 18, and the lead connecting piece 19a on theside of the wire connecting portion 20 are initially connected to eachother through the connecting piece 19b. In the primary and secondarymoldings, therefore, the parts such as the overlap contact portion 18,the device mounting portion 19, and the wire connecting portion 20 canbe collectively handled as a single part, i.e., the voltage-detectionterminal unit 17. As a result, the number of parts and the man-hour canbe reduced, and the production cost can be lowered.

FIGS. 21(A) and 21(B) show other embodiments of the resin leakageinspection holes of the overlap contact portion, respectively.

The resin leakage inspection holes 18b' of FIG. 21(A) are formed asquadrant-like slits which are very larger in size than the resin leakageinspection holes 18b. The four holes are symmetrically disposed aroundthe bolt insertion hole 18a. The resin leakage inspection holes 18b' arepositioned diametrically outside a dish portion 26a of the bolt 26.

In the embodiment shown in FIG. 21(B), the overlap contact portion 18'is formed into a doughnut-like disk shape, and the spaces between theround outer peripheral edge 18e and the inner edge of the rectangularhole 12' are used as resin leakage inspection holes 18b".

Both the resin leakage inspection holes 18' and 18b" have an area whichis very larger than the area of the resin leakage inspection holes 18b,and look like a window.

In the case where a large hole (or a window) such as the resin leakageinspection holes 18' or 18b" is formed, when the molten resin injectedinto the molds in the insert molding reaches the inspection holes 18' or18b", the resin is abruptly released and its pressure is lowered. Thisperfectly prevents the resin from entering toward the center portion(i.e., the bolt insertion hole 18a), thereby eliminating a failure ofcontinuity between the bus bar 16 and the voltage-detection terminalunit 17.

Returning to FIG. 20(B), in the connecting plate 10, the whole of theparts (the lead connecting pieces 19a at the sides, the wire connectingportion 20, and the like) to which the fuse 21 is connected are bound bythe molded resin board 11. When an external force such as an impact or apressing force is applied to a part of the connecting plate 10,therefore, stress propagates via the resin board 11 to reach theconnection portions such as the solder 25, thereby producing a dangerthat a trouble such as a crack of the solder occurs.

FIG. 22 shows a structure for relaxing such stress. FIG. 22(A) is aperspective view of the fuse mounting window 14, and FIG. 22(B) is alongitudinal section view taken along the line X--X of FIG. 22(A).

Rectangular slits 58 are disposed around the whole periphery of thewindow frame 14' of the primary molded resin board 11B (11C) in theprimary molded product P₁. The reference numeral 58a denotes ties (inthe illustrated example, four ties) corresponding to spouts for a resinin the molding of the window frame 14'. A middle portion of each of thelead connecting pieces 19a at the ends of the device mounting portion 19in the voltage-detection terminal unit 17 is located in one of the slits58.

Even when an external force acts on the primary molded product P₁ (orthe secondary molded product P₂), therefore, stress due to the force isinterrupted by the slit 58, and the window frame 14' and the internalparts such as the solder 25 are not affected by the stress.

Referring to FIG. 22(A), in order to eliminate the ties 58, the resinfilling hole (see FIG. 18) in the molds may be disposed for each of thewhole of the molds and the formation of the window frame. According tothis configuration, the window frame 14' has a floating island of acertain kind which is supported by the lead connecting pieces 19a atboth the sides, and hence the solder 25 inside the frame is perfectlyunaffected by the outside.

FIGS. 23(A) and 23(B) show another embodiment of the structure forrelaxing stress. FIG. 23(B) is a section view taken along the line X--Xof FIG. 23(A).

A window frame 14" is pre-inserted aside from the primary molding (seeFIGS. 9 and 10) of the harness 34 for a plate.

The pre-insert may be previously prepared by using the voltage-detectionterminal unit 17 having the device mounting portion 19. Therefore, theprimary molding (main insert) may be performed by using the window frame14".

According to this configuration, an interface 59 is formed between theresin portion (the window frame 14") of the pre-insert and that (theprimary molded resin board 11B, 11C) of the main insert. Even whenbending stress or the like is applied, therefore, a gap is formed in theportion and the propagation of the stress is suppressed. The resinmaterials of the pre-insert and the main insert may be identical with ordifferent from each other. From the view point of enhancement of thesuppression effect, it is preferable to use different materials.

FIGS. 24(A) to 24(C) show another embodiment of the structure forrelaxing stress. FIG. 24(A) is a perspective view of a voltage-detectionterminal unit, FIG. 24(B) is a section view showing a state of attachingthe terminal to the window frame 14' of FIG. 22(A), and FIG. 24(C) is asection view showing a state of attaching the terminal to the windowframe 14" of FIG. 22(B).

The voltage-detection terminal unit 17' shown in FIG. 24(A) is differentfrom the voltage-detection terminal unit 17 in that a second connectionpiece 18d' which is upward cranked is disposed between the devicemounting portion 19 and the wire connecting portion 20, and that, as aresult of this disposition, the center axis of the wire connectingportion 20 is in a plane which is substantially flush with the overlapcontact portion 18.

As shown in FIG. 24(B), the bent portion serving as the secondconnection piece 18d' is located in the slit 58 in the outer peripheryof the window frame 14'. Alternatively, as shown in FIG. 24(C), the bentportion is located at the interface 59 between the window frame 14" ofthe pre-insert and the primary molded resin board 11B and the like ofthe main insert.

In the case of FIG. 24(B), the existence of the slit 58 and the bentportion surely blocks the transmission of stress to the lead connectingpiece 19a in the window frame 14'.

In the case of FIG. 24(C), the window frame 14" of the pre-insert can bemoved (or slid) together with the fuse 21 inside the frame, and thisportion can similarly block the transmission of stress.

What is claimed is:
 1. A connecting plate for a battery holdercomprising:a bus bar which interconnects a plurality of batteries; avoltage-detection terminal unit which is connected to said bus bar andthrough which a voltage of a desired one of said batteries is detected;an electric wire connected to said voltage-detection terminal unit; anda molded resin board to which these components are integrally fixed,wherein said voltage-detection terminal unit includes a resin leakagepreventing piece formed at a side edge of a contact portion of saidvoltage-detection terminal unit and opposed to said bus bar, said resinleakage preventing piece serving also as a positioning piece withrespect to said bus bar.
 2. A connecting plate for a battery holderaccording to claim 1, further comprising resin leakage inspection holesformed around a bolt insertion hole at a center of said contact portionof said voltage-detection terminal unit opposed to said bus bar.
 3. Aconnecting plate for a battery holder according to claim 1, furthercomprising a device mounting portion onto which a circuit protectingdevice is to be mounted, said device mounting portion being integrallyformed with said voltage-detection terminal unit between said contactportion and an electric wire connecting portion, said device mountingportion being exposed to an outside through a device mounting windowwhich is opened in said molded resin board, and said circuit protectingdevice mounted onto said device mounting portion is housed in saiddevice mounting window.